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Agriculture and Rural Land Use
Unit 3
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I. Origins of Agriculture
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A. Origins of Agriculture
1. Agriculture is the deliberate modification of Earth’s surface through the cultivation of plants and/or rearing of animals. 2. Exact invention of agriculture is unclear, but it likely diffused from many hearths.
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B. The First Agricultural Revolution
1. Geographer Carl Sauer suggests that the first tropical plant domestication occurred in S and SE Asia more than 14,000 years ago. 2. Seed crops marked the first AR, which likely originated in the Fertile Crescent. 3. Domestication of animals likely occurred about 8,000 years ago.
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C. The Second Agricultural Revolution
1. Moved agriculture beyond subsistence farming to generate surpluses needed to feed thousands of people working in factories. 2. Great Britain’s Enclosure Act encouraged field consolidation into large, single-owner holdings. 3. New technologies transformed farming, and there were advances in breeding livestock.
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C. The Third Agricultural Revolution
1. Called the Green Revolution. 2. Since the 1930s, agricultural scientists experimented with technologically manipulated seed varieties to increase crop yields. 3. The Green Revolution has been criticized for its use of genetically modified crops and chemical fertilizers and pesticides. 4. GMOs are found in 75% of all processed foods in the US.
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II. Commercial and Subsistence Agriculture
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A. Commercial vs. Subsistence Agriculture
1. Subsistence = produced mainly for the farm families survival, most common in less developed countries 2. Commercial = produced mainly for sale off the farm, most common in more developed countries 3. Commercial and subsistence agriculture is distinguished by purpose of farming, percentage of farmers in the labor force, use of machinery, farm size, and relationship of farming to other businesses.
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III. Variations in Food Consumption
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A. Diet Consumption of food varies around the world primarily based on physical geography and level of socioeconomic development. Developing regions typically differ most in their primary sources of protein consumed.
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B. Nutrition and Hunger The UN estimates that 850 million people are undernourished. 99% of those people are located in developing countries.
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IV. Distribution of Agriculture
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A. Shifting Cultivation
Two features: land is cleared by slash-and-burn agriculture, and land is tended for only a few years at a time. Most often occurs in tropical rainforest regions, such as SE Asia, Central Africa, and Brazil.
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B. Intensive Subsistence
Found in areas with high population and agricultural densities, especially in East, South, and Southeast Asia. To maximize production, little to no water is wasted.
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C. Mixed Crop and Livestock Farming
Livestock fed with crops grown on same farm, ¾ of income is from sale of animal products. Involves crop rotation, which helps maintain fertility of land. Common products are corn and soybeans.
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D. Dairy Farming Primarily in NE US, SE Canada, and NW Europe.
60% of the world’s milk comes from these areas. Must be close to their market area because it’s highly perishable.
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E. Grain Farming and Livestock
Largest commercial producer of grain is the US (KS, CO, OK, MT, WA, ND, SD). Livestock ranching is practiced in US, Brazil, Argentina, Uruguay, and Australia.
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F. Plantation Farming Usually involves the production of one crop.
Common in many tropical areas, like Latin America, Africa, and Asia. Examples: bananas, sugarcane, coffee, tea, cocoa, cotton, rubber, palm oil, etc.
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V. Von Thünen Model
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A. Von Thünen Model - Defined
This model shows how distance from a city or market affects the choice of agricultural activity in a uniform landscape. Even when agricultural production doesn’t conform perfectly to the model, concern about land use and transportation costs still explains agricultural patterns today.
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B. Von Thünen Model Layer 1: Urban Center/Market
Horticulture and Dairy Farming Forestry Grains/Field Crops Extensive Ranching and Grazing
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VI. Why Farmers Face Economic Challenges
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A. Challenges for Commercial Farmers
Overproduction – food supplies increase despite constant demand Sustainable agriculture – managing land properly Population growth – Boserup Thesis states that population growth compels subsistence farmers to consider new farming approaches that can produce enough International trade – LDCs need to grow crops people in MDCs want (coffee, tea, cocoa) Drug Crops – cocaine and marijuana in South America and opium and heroin in Afghanistan, Myanmar, and Laos
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B. Strategies to Increase Food Supply
Expanding agricultural land – desertification in the Sahel Increasing productivity – higher-yield seeds, fertilizers, and the Green Revolution Identifying new food sources – cultivating oceans, developing higher-protein cereals, and improving palatability of foods Increasing trade
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